Complex aircraft of today require electronic instruments that are relatively simple for a pilot to use while being relatively precise. Given the complexity of aircraft systems and the relatively cramped confmes of the flight deck, it is desirable to have a large amount of information displayed to a pilot in a relatively compact format.
One such display unit for providing information to a pilot is a Primary Flight Display (PFD). The PFD displays flight critical information to the pilot on a relatively compact display screen. The information displayed often includes the air speed indicator, the altimeter, the vertical speed indicator, the artificial horizon indicator, and other appropriate displays. Additionally, the PFD may display navigational equipment displays such as a compass, a radar screen, a flight map, and a heading indicator.
Any or all of these displays may be accompanied by a multitude of selectable menu items, the menu items relating to aircraft settings. Many of these aircraft settings have selectable numerical values related therewith. Throughout a flight program, a pilot is presented with a multiplicity of menu items and must be able to conveniently and quickly select and modify any of the available aircraft settings.
Conventionally, menu items are selected by pressing one of a number of line select keys (LSKs). The LSKs are often located on the PFD, a menu item is chosen by pressing the LSK adjacent to the desired menu item. The display shows the menu item associated with the depressed LSK as a highlighted item. To modify the value of the menu item chosen, a pilot or user manipulates a separate knob to change a selected value.
The use of LSKs in combination with a separate control knob causes difficulties for a pilot. A pilot needs to keep at least one hand on the control column at all time. If, for example, the pilot needs to select a LSK located on the left side of the PFD (the PFD being located directly in front of the pilot), the pilot places his right hand on the control column and makes the LSK selection with his left hand. The pilot then affects the change to the selected value by turning a control knob located on a Display Control Panel (DCP), the DCP being located to the right of the PFD. Therefore, the pilot must place his left hand on the control panel and reach over with his right hand to make the necessary change to the selected menu item value. This process is non-ergonomic and requires excessive movement to make a change to the aircraft settings.
Accordingly, there is a need for an integrated device to make menu item selections and to subsequently make changes to the selected menu item values. There is also a need for an ergonomic selection device which minimizes movement inside the cockpit. Further still there is a need for a menu item selection and modification device, whereby the pilot's hand is not required to leave the device throughout the menu selection and value modification process. Further still there is a need for a remote menu operation device that does not require line select keys located adjacent the display device. Even further still, there is a need for a control knob on a display control panel (DCP) of an aircraft, and a method for using the control knob to select menu items on a Primary Flight Display (PFD) of the aircraft, and to modify the value of the selected menu item by use of a button on the control knob or other means integral to the knob (such as pushing or pulling the knob). As one knob will be used to select which items are active and to set values associated with some items, a means to differentiate the activity must exist.